[PATCH v4 1/4] rtc: OMAP: Add system pm_power_off to rtc driver
AnilKumar Ch
anilkumar at ti.com
Fri Dec 14 01:03:14 EST 2012
From: Colin Foe-Parker <colin.foeparker at logicpd.com>
Add system power off control to rtc driver which is the in-charge
of controlling the BeagleBone system power. The power_off routine
can be hooked up to "pm_power_off" system call.
System power off sequence:-
* Set PMIC STATUS_OFF when PMIC_POWER_EN is pulled low
* Enable PMIC_POWER_EN in rtc module
* Set rtc ALARM2 time
* Enable ALARM2 interrupt
Signed-off-by: Colin Foe-Parker <colin.foeparker at logicpd.com>
[anilkumar at ti.com: move poweroff additions to rtc driver]
Signed-off-by: AnilKumar Ch <anilkumar at ti.com>
---
Documentation/devicetree/bindings/rtc/rtc-omap.txt | 5 ++
drivers/rtc/rtc-omap.c | 74 +++++++++++++++++++-
2 files changed, 78 insertions(+), 1 deletion(-)
diff --git a/Documentation/devicetree/bindings/rtc/rtc-omap.txt b/Documentation/devicetree/bindings/rtc/rtc-omap.txt
index b47aa41..8d9f4f9 100644
--- a/Documentation/devicetree/bindings/rtc/rtc-omap.txt
+++ b/Documentation/devicetree/bindings/rtc/rtc-omap.txt
@@ -6,6 +6,10 @@ Required properties:
- interrupts: rtc timer, alarm interrupts in order
- interrupt-parent: phandle for the interrupt controller
+Optional properties:
+- ti,system-power-controller: Telling whether or not rtc is controlling
+ the system power.
+
Example:
rtc at 1c23000 {
@@ -14,4 +18,5 @@ rtc at 1c23000 {
interrupts = <19
19>;
interrupt-parent = <&intc>;
+ ti,system-power-controller;
};
diff --git a/drivers/rtc/rtc-omap.c b/drivers/rtc/rtc-omap.c
index 6009714..e6d4878 100644
--- a/drivers/rtc/rtc-omap.c
+++ b/drivers/rtc/rtc-omap.c
@@ -72,6 +72,14 @@
#define OMAP_RTC_KICK0_REG 0x6c
#define OMAP_RTC_KICK1_REG 0x70
+#define OMAP_RTC_ALARM2_SECONDS_REG 0x80
+#define OMAP_RTC_ALARM2_MINUTES_REG 0x84
+#define OMAP_RTC_ALARM2_HOURS_REG 0x88
+#define OMAP_RTC_ALARM2_DAYS_REG 0x8c
+#define OMAP_RTC_ALARM2_MONTHS_REG 0x90
+#define OMAP_RTC_ALARM2_YEARS_REG 0x94
+#define OMAP_RTC_PMIC_REG 0x98
+
/* OMAP_RTC_CTRL_REG bit fields: */
#define OMAP_RTC_CTRL_SPLIT (1<<7)
#define OMAP_RTC_CTRL_DISABLE (1<<6)
@@ -93,15 +101,21 @@
#define OMAP_RTC_STATUS_BUSY (1<<0)
/* OMAP_RTC_INTERRUPTS_REG bit fields: */
+#define OMAP_RTC_INTERRUPTS_IT_ALARM2 (1<<4)
#define OMAP_RTC_INTERRUPTS_IT_ALARM (1<<3)
#define OMAP_RTC_INTERRUPTS_IT_TIMER (1<<2)
+/* OMAP_RTC_PMIC_REG bit fields: */
+#define OMAP_RTC_PMIC_POWER_EN_EN (1<<16)
+
/* OMAP_RTC_KICKER values */
#define KICK0_VALUE 0x83e70b13
#define KICK1_VALUE 0x95a4f1e0
#define OMAP_RTC_HAS_KICKER 0x1
+#define SHUTDOWN_TIME_SEC 2
+
static void __iomem *rtc_base;
#define rtc_read(addr) readb(rtc_base + (addr))
@@ -290,6 +304,56 @@ static int omap_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alm)
return 0;
}
+/*
+ * rtc_power_off: Set the pmic power off sequence. The RTC generates
+ * pmic_pwr_enable control, which can be used to control an external
+ * PMIC.
+ */
+static void rtc_power_off(void)
+{
+ u32 val;
+ struct rtc_time tm;
+ unsigned long time;
+
+ /* Set PMIC power enable */
+ val = readl(rtc_base + OMAP_RTC_PMIC_REG);
+ writel(val | OMAP_RTC_PMIC_POWER_EN_EN, rtc_base + OMAP_RTC_PMIC_REG);
+
+ /* Read rtc time */
+ omap_rtc_read_time(NULL, &tm);
+
+ /* Convert Gregorian date to seconds since 01-01-1970 00:00:00 */
+ rtc_tm_to_time(&tm, &time);
+
+ /* Add shutdown time to the current value */
+ time += SHUTDOWN_TIME_SEC;
+
+ /* Convert seconds since 01-01-1970 00:00:00 to Gregorian date */
+ rtc_time_to_tm(time, &tm);
+
+ if (tm2bcd(&tm) < 0)
+ return;
+
+ pr_info("System will go to power_off state in approx. %d secs\n",
+ SHUTDOWN_TIME_SEC);
+
+ /*
+ * pmic_pwr_enable is controlled by means of ALARM2 event. So here
+ * programming alarm2 expiry time and enabling alarm2 interrupt
+ */
+ rtc_write(tm.tm_sec, OMAP_RTC_ALARM2_SECONDS_REG);
+ rtc_write(tm.tm_min, OMAP_RTC_ALARM2_MINUTES_REG);
+ rtc_write(tm.tm_hour, OMAP_RTC_ALARM2_HOURS_REG);
+ rtc_write(tm.tm_mday, OMAP_RTC_ALARM2_DAYS_REG);
+ rtc_write(tm.tm_mon, OMAP_RTC_ALARM2_MONTHS_REG);
+ rtc_write(tm.tm_year, OMAP_RTC_ALARM2_YEARS_REG);
+
+ /* Enable alarm2 interrupt */
+ val = readl(rtc_base + OMAP_RTC_INTERRUPTS_REG);
+ writel(val | OMAP_RTC_INTERRUPTS_IT_ALARM2,
+ rtc_base + OMAP_RTC_INTERRUPTS_REG);
+}
+
static struct rtc_class_ops omap_rtc_ops = {
.read_time = omap_rtc_read_time,
.set_time = omap_rtc_set_time,
@@ -327,12 +391,16 @@ static int __init omap_rtc_probe(struct platform_device *pdev)
struct resource *res, *mem;
struct rtc_device *rtc;
u8 reg, new_ctrl;
+ bool pm_off = false;
const struct platform_device_id *id_entry;
const struct of_device_id *of_id;
of_id = of_match_device(omap_rtc_of_match, &pdev->dev);
- if (of_id)
+ if (of_id) {
pdev->id_entry = of_id->data;
+ pm_off = of_property_read_bool(pdev->dev.of_node,
+ "ti,system-power-controller");
+ }
omap_rtc_timer = platform_get_irq(pdev, 0);
if (omap_rtc_timer <= 0) {
@@ -385,6 +453,10 @@ static int __init omap_rtc_probe(struct platform_device *pdev)
platform_set_drvdata(pdev, rtc);
dev_set_drvdata(&rtc->dev, mem);
+ /* RTC power off */
+ if (pm_off && !pm_power_off)
+ pm_power_off = rtc_power_off;
+
/* clear pending irqs, and set 1/second periodic,
* which we'll use instead of update irqs
*/
--
1.7.9.5
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